Originally Posted by woodg
My friend has used SuperSim (
http://www.nowgsm.com/supersim.htm). It copies the contents of your SIM (up to 16 SIMs, in fact) to the SuperSIM card. He has used it to copy a Telstra SIM (from Australia) and a T-Mobile SIM (from the USA). When he puts the SuperSIM in the cell phone it adds another menu item that allows him to swap from one "sim" to another. It seems to work OK. I've just ordered one myself.
Hope this helps,
Glenn
Just a word of warning: do NOT use this on a modern sim card (like from T-mobile or Cingular), they use newer sim cards and attempting to copy the sim WILL block the card requiring a new one to be issued.
These cloning kits only work on very old sims, perhaps if you still have an old Omnipoint or Voicestream sim it could work, but I most certainly don't advise you trying it...